Environment and Breast Cancer: Science Review

Serum organochlorine levels and breast cancer: a nested case-control study of Norwegian women
Ward, E. M., Schulte, P., Grajewski, B., Andersen, A., Patterson, D. G., Jr., Turner, W., Jellum, E., Deddens, J. A., Friedland, J., Roeleveld, N., Waters, M., Butler, M. A., DiPietro, E., Needham, L. L. Cancer Epidemiology, Biomarkers and Prevention. 2000. 9:12, 1357-67.

Topic area
Environmental pollutant - Pesticides, organochlorine, PCB, DDE, DDT, HCH, HE
Environmental pollutant - Pesticides, organochlorine, PCB, DDE, DDT, HCH, HE
Study design
Other: serum samples from blood bank
Other: serum samples from blood bank
Funding agency
DOD
DOD

Study Participants
Number of Cases
150
150
Menopausal Status
Post menopausal
The menopausal status of women included in this study is listed here.
Pre menopausalPost menopausal
Number of Controls
Controls: 150
Controls: 150
Participant selection: Inclusion and exclusion criteria
Criteria used to select participants in the study.
Cases were selected among the female serum bank donors who were working outside the home or were residents on farms, were identified through the Norwegian Cancer Registry as having breast cancer, and had a blood sample taken 2 or more years before diagnosis.
Controls were matched based on date of sample collection and date of birth. Cases were alive and free of cancer (except for basal cell carcinoma of the skin), as of the date of cancer diagnosis.
Exposures investigated
Lipid-adjusted serum concentrations of organochlorines.
Lipid-adjusted serum concentrations of organochlorines.
How exposure was measured
Biological
Biological

Statistical Analysis
Breast cancer outcome investigated
Primary breast cancer
Primary breast cancer
Ethnic groups with separate analysis
If this study provided a separate analysis by ethnic or racial group, the groups are listed here.
No
Confounders considered
Other breast cancer risk factors, such as family history, age at first birth, and hormone replacement therapy use, that were taken into account in the study.
Occupational category, age at first birth, number of births prior to donation of blood sample, region of residence, and region of birth.
None of the covariates changed either the magnitude or direction of the unadjusted ORs.
Genetic characterization included
If the study analyzed relationships between environmental factors and inherited genetic variations, this field will be marked “Yes.” “No”, if not.
No
Description of major analysis
For analytes with over 90% of samples above the limit of detection, conditional logistic regression was used to estimate ORs relating each analyte to breast cancer. For analytes with less than 90% of samples above the limit of detection, conditional logi
For analytes with over 90% of samples above the limit of detection, conditional logistic regression was used to estimate ORs relating each analyte to breast cancer. For analytes with less than 90% of samples above the limit of detection, conditional logi
Strength of associations reported
None of the ORs were significantly elevated, and no evidence of increased risk was seen with increasing doses. For most compounds the risk decreased with increasing doses, and mean levels were higher among controls.
OR for the highest quartile of p,p'-DDE: 1.2 (95% CI not presented).
OR for the highest quartile of Total PCBs: 0.5 (95% CI not presented).
Stratification did not lead to significant differences between cases and controls for the mean concentrations of any compounds.
None of the ORs were significantly elevated, and no evidence of increased risk was seen with increasing doses. For most compounds the risk decreased with increasing doses, and mean levels were higher among controls.
OR for the highest quartile of p,p'-DDE: 1.2 (95% CI not presented).
OR for the highest quartile of Total PCBs: 0.5 (95% CI not presented).
Stratification did not lead to significant differences between cases and controls for the mean concentrations of any compounds.
Results Comments
Samples from individuals who developed breast cancer less than two years after providing the blood sample were excluded from the analysis to minimize the possible effect of the cancer on the serum pesticide concentrations.
Samples from individuals who developed breast cancer less than two years after providing the blood sample were excluded from the analysis to minimize the possible effect of the cancer on the serum pesticide concentrations.

Author address
Division of Surveillance, Hazard Evaluations and Field Studies, National Institute for Occupational Safety and Health, Cincinnati, Ohio 45226, USA.
Division of Surveillance, Hazard Evaluations and Field Studies, National Institute for Occupational Safety and Health, Cincinnati, Ohio 45226, USA.
Controls participation rate
Not reported
Not reported